Related InterviewSolutions

• State the unit of magnetic field in terms of the force experienced by a current carrying conductor placed in a magnetic field
• Name and state the law which is used to determine the direction of force on a current carrying conductor placed in a magnetic field.
• How is the magnetic field due to a straight current carrying wire affected if current in wire is (a) decreased, (b) reversed?
• State a law, which determines the direction of magnetic field around a current carrying wire.
• Suggest two ways in an a.c. generator to produce a higher e.m.f.
• In an a.c. generator the speed at which the coil rotates is doubled. How would this affect (a) the frequency of output voltage, (b) the maximum output voltage is doubled.
• The following diagram in Fig. 10.44 shows a coil X connected to a sensitive centre –zero galvanometer G and a coil P connected to a battery through a switch S.(a) Describe the observation when the switch S is (i) closed suddenly, (ii) then kept closed, (iii) finally opened.(b) Name and state the law which explains the above observations.
• What determines the frequency of a.c. produced in a generator?
• State two dis-similarities and one similarity between a d.c. motor and an a.c. generator.
• The following diagram shows a spiral coil wound on a hollow carboard tube AB. A magnetic compass is placed close to it. Current it switched on by closing the key. (a) What will be the polarity at the ends A and B? (b) How will the compass needle be affected? Give reason.